Hollow blast-grate.



E. x. ,-A. vAN nimm;` HoLLow vBLAST GRATE. unicum Elgin D Eclzz. 1910.

Patented July 4, 1916.

3 SHEETS-snm a. l

IN'VENTOR WITNESSES I PAULUS J. A. vAN DEINSE, OF' GREENVILLE, MICHIGAN HOLLOW 'BLAsrGRATE Specification of Letters Platent.

1,1 stress To all ll/l'wm 'it mf/,j/ concern:

,e it known that I, PAULUs J. A. VAN Diiixsiz, a citizen of the United States, re-

siding at Greenville, in the county of Montv calm and State of Michigan, have invented -a new and useful Hollow Blastfrate, of Q comprises a top member 1, a bottom member whiclrthe'following is a specification.

Thls invention has reterence to improvements in. grates wherein alternate blast and' draft bars are employed, and the object of the present invention is to provide a str'ucture wherein there is little or no likelihood oil the streams of air issuingiroin the blast bars being diverted through the draft bars, or between them and the draft bars toward the ash pit', or the blast outlets becoming choked, or the blast bars becoiningilled rto any material extentwith ashes soas to reduce `their effective cross-sectional area. Furthermore. in the present invention the .bars are well protected from' damage due to the efforts of heat, the blastoutletsmay Y,

be made to diffuse the blast, if desired, and the automatic removal of ashes' from"the grate through the draft bars is facilitated.

ln accordance withkthe present invention the blast bars have rigid or corrugated fuel sustaining surfaces with blast openings' ot' appropriate shape in the ridges,` while' the draftbars are similarly sha-pcd with`open-4 ings in the valleys, while the meeting edges ofthe two types of bars are preferably so formed withrespect one to tlieother lthat there is no likelihood of the blast streams,- finding escape therethroi'igh rather than the grate toi different types of fuel whileV the salient points of the'iinvention are still retained.

In the/drawings :s-Figure 1 is aplan view of associated blast and-draft bars, a single blast bar and a single draft bar only being' shown. Fig'. 2 is a section on :the line 2-'-2 of Fig. 1.. Fig. il is a detailed section-of a modified Aform. Fig. 3 is'a'seotion'of 'as.

sociated draft and blast bars sho4 ing a I haveno bottom member.

.Patented July a, 191e.

Application tiled iecember 27, 1910. SerialNo. 599,615.

slightly modified construction. Fig. 4 is a bottom plan view of a blast grate barfl F i is a section on the line of Fig. 4.-

Referring to the drawings, there is. shown a blast bar A and a draft bar B. In the particular structure. shown the blast bar i 2 and side members 3 joining the top and bottom members, and suitable end walls 4f are provided whereby the blast bar is formed with an interior chamber into which the air iin-der pressure may be directed. In

the particular structure shown, the side members 3 approach toward the bottom 2, but this is not a mandatory form. i

The top 1 is shown as corrugated, the corriigations running longitudinally of the bar, but it will bennderstood that any form of -npper surface may be adopted, whereby there are formed ridges 5 and'valleys 6,

whether the ridges be lengthwise of the bar or extend in any other direction, such changes over the showing of' the drawing being vdetermined by theparticular conditions to be met, since some kinds of fuel re- `quire different` forms .of` grate bars than vVohers. The blast barA is provided with series of perforations 7 shown in Fig.4 2 as of equall diameter throughout, and in Fig.- 2 `astapering' toward the upper end, and: these perfr'ations may be circular" or any other desired shape, the Yparticular form of the passages"7 being determined by the coni ditions 'to be niet, 'passagesl'rfwith circular outlets answering for certain kinds'of fuel, while outlets `of other shapeslare advanta-Y geous .withfuel ofother kinds,`andin some instances those of lequal .diameter throughn ont' are to be preferred 4and under other conditions those of greater diameter at one end than' the other are preferable,`bnt in any instance the outlets of the passages 7 are located at the highest pointsfof the ridges 5 whatever be the shape of such passages and outlets. `By preference the .passages rin one ridge 5 alterna'ite with the passages '7 in thenext adjacent ridge or ridges, but even in this respect the particular agxaange- `ment is not mandatory. l

The draft bars B have each a topmeifnber'4 8 and Iside members 9 with transversel Webs 10 where neededfor strength, but these bars` The draft bars B also have the top member 8 corrugated or otherwise formed to ro'duce rdgesll and valleys 12 between tiem. The contour of,

the likelihood the fuel supporting surface of the bars B may correspond to that of the bars A or may difi'er-` but instead of' having passages opening at the tops of the ridges, each draft bar ll has passages 13 opening at the lowest point of the valleys. The openings lil are in spaced relation one to the other in each valley, and those of one valley may alternate with those of the next adjacent valley or valleys. but this arrangement is not maiulatm-y though eliieient in practice. Moreover, it is advisable, though not necessary, that the series ot' passages 7 adjacent the edge of a blast bar should have the passages alternate with the adjacent passages ot the next draft har in order.

The passages 7 in Fig. 2 are shown as of eipial diameter throughout their length, while the blast bar A of' Fig. 3 is shown with passages T having the exit opening 14 expanded. Here again the relative size and shape oi' the blast passage will depend upon the fuel to be used. 1n thc structureA of Fig. 2 the hlast is'directed in a condensed stream into the l'uel. In Fig. 3 the blast is permitted to expand at the end of the blast passage toward the fuel, and ronsequently enters the latter in an expanding stream. f

rlhtsc two forms of blast passages together 'with that shown in Fig. 2 may be taken as typical of any suitable form may be lound expedient for the kind of fuel used.

Since the body of fuel on the grate offers resistance to the passage of thhlastywhere the grate is overloaded, the streams issuing from thea.l passages 7 or 'i'u adjacent the longitudinal edge of the blast bar may find their way through the spaces between the blast bar and the next adjacent draft bar,

i la. streams naturally following the path 0f least resistance. To overcome this,`the blast and draft bars may be provided with lapjoints where meeting. For this purpose the blast har A 0i' Fig. Q is shown as provided with a longitudinal flange l5, while the draft bar has a corresponding recess or groove lli. and the'said draft bar may have a longitudinal flange 17 underriding the flange 15, while the blast bar is provided with a matching groove 18 adapted to rceelve tll'e flange 17. This will form an overlapping joint through which little or no air will find its way from the blast openings ad# jaent to the joint Under sonic circumstances a plain butt joint may beprovidcd between the two bars A and B, as indicated at 19 in Fig. 3. These two types of joint may be taken as indicative. of any suitable joint structure between the two types of bars.

lly lfuaiting'the blast passages at the tops ol the ridge: the danger ot choking these passages with ashes or particles of fuel, and

reaching the interior oi thc blast bar, are

of ashes or otter matten reduced to a minimum. Another great advantage oi' so locating the blast passages is that if the valleys become filled with ashes. which, being an excellent noircombu'tor ot' heat, protects the top oi the bar, thereby1 increasing its durability. were located in the valleys or in the inclined faces, the parts adjacent to or opposite the outlets would become intensely hot, since the action ot' the blast is that of a blow-pipe.

In a hollow blast grate the draft bars are,

designed primarily for the escape of ashes through them, and consequently thepas sages 13 expand toward the lower end, so that particles of' ashes lind no lodgment therein, but any ashes which enter the. passage 13 will fall therethrough to the ash pit, the bottom of the draft bar being open. Moreover, the passages lil are located in the valleys between the ridgespand the ashes naturally gravitate to these points. The draft bars become covered with ashes, so that the valleys are filled thcrewitli', the ashes forming a sort of protective coating as in the blast bars. ln the case ol' the draft bars the passages 13 may further even become temporarily bridged over with ashes, thus preventing any material loss of the air streams by diversion tlnlough the draft bars.

The openings through the blast hars are solely for the purpose of introdiuzing air and by forming them through the ridges, so as to open at the tops of such ridges, they are kept markedly free from ashes. l'n the draft bars the openings are for the dis posal of'ashes, and are so located and of such shape to facilitate the directing of the ashes to the openings and the passage of such ashes through the openings.

Each blast bar is formed with a passage lll'throngh the bottom wall 2, and this'pa sage is surrounded with a. nipple 20, cored out as shown at 22 to 'form an annular shoulder or flange 23 which may be. roamed out to snuglyiit a tube 24 abutting against the bottorn 2 at the opening 1l), the interior of the tube and the openingr 19 heilig of the same dia ieter. This is the preferred form of inlet f'or thc blast bar but other means for introducing the air into the blast bar may be used. The bottom 2 has :mother opening 25 preferably remote from the inlet l9,and this opening 25 is normally covered by a slide QG held to the bar by a guide plate 27 fast to the bottom 2 of the blast bar and provided with a passage matching the opening The slide 26 has fast thereto an eye 29 near one end normally within a recess 31) in the corresjnmding end of.t the plate 2T, while a stop pin 3l projectinor from the bottoni 2 limits the movement o the slide to uncover the opening The slide 2li is moved to the open position when it is desired to blow out accumulations from the blast bar.

if tho outletsbars having passages'therethrough openingy 1. A grate composed of blast bars and draft bars in alternation, each. having the fuel supporting surface' formed with alter* nate ridges and valleys, the blast bars having airI passages therethrough opening at the .highest points' of the.ridges, and the draft bars having passages therethrough opening at the bottomsof the valleys.,

2. A grate composed of blast bars and draft bars in valternation each having the fuel supporting surface formed with alternate ridges and valleys, thebla'st bars having air passages therethroughopening at the Ihighest points' of the ridgesfand the draft bars having passages therethrough opening at the bottpms of the valleys, theA meeting edges of the blast and draftbars being in overlapping relation.

f3. A grate composed of blast bars and draft bars in alternation, each having the fuel supporting surface formed `with alternate ridges and valleys, the blast bars having air passages therethrough opening at the highest points of the ridges,

and the draft at the bottomsof the valleys, the meeting bars being formed with matching longitudinal Hanf'ges 'and grooves, Ythe ange of one' bar seating' in the matching groove of the'other bar.

4; In a blastI grate, a blast bar having its fuel sustainingsurface provided with alternating ridges and valleys and having-blast passages wlth their exit openings at' the highest points of the ridges and each therer eXpa-nding'to direct an expanded stream of.

air into the fuel. u

Av grate composed of blast bars and draftl bars in alternation and having the fuel sustaining. surface formed. into `alternate ridges and valleys, the, blast bars having air passages therethrough opening at the sumand each draft bar having openings through f its fuel sustaining surfacer at the bottoms only ofthe valleys, the openings through the draft bars expandingin a direction away from the fuel sustaining surface.

7. Agrate composed of blast bars and draft barsin alternation an'd having the fuel sustaining surface formed int-o alternate ridges andvalleys, the blast bars having an' i passages therethrough' opening atthe'surnmits of theridges.

'In testiuj1ony,that I claim the foregoing as my own, `I have hereto affixed my signa- `ture in the presence of two witnesses.

PAULUS J'. A. VVAN D'EINSE. Witnesses CRAIG VALKER, HELEN M. EnsALL. 

